Torchiere floor lamp fixtures such as that shown in FIG. 3, and similar fixtures manufactured to hold halogen-tungsten bulbs 80 with R7s lampholders in a bowl 50 have been discovered to pose significant fire hazards. The straight halogen-tungsten bulbs 80 for which such lamps were designed use significant energy (usually 300 or 500 Watts) and generate a significant amount of heat. When such lamps have been placed too close to draperies or other flammable materials the heat of the high--wattage halogen-tungsten bulbs has often been sufficient to cause the materials to catch fire. Similarly, when children or pets knock such lamps over onto flammable surfaces, fires have sometimes ignited. Not only do halogen-tungsten straight bulbs 80 of this type present a fire hazard and consume significant energy, they also do not have a long life. Usually such bulbs last only a thousand hours.
However, tens of millions of torchiere style floor lamp fixtures using this type of bulb have been sold around the world. The popularity of this type of fixture has made it difficult to use existing compact fluorescent bulbs as a replacement for several reasons. First, as seen in FIG. 3, the lampholder R7s for the straight halogen-tungsten bulbs 80 of this type of torchiere floor lamp fixture has two electrical contacts, R7s1 and R7s2 built into it. Existing compact fluorescent lamps (CFLs) were created to replace ordinary incandescent bulbs in standard tungsten incandescent lamps use E26, E27, B22 and other normal lampholders for conventional incandescent lamps. These usually consist of prongs connecting the fluorescent tube to a ballast which, in turn is fixed in a lampholder designed to screw into ordinary incandescent light fixtures. Consequently, the electrical connections in the lampholder R7s of torchiere-style fixtures do not fit those in existing CFL lamps and ballast replacement units.
Since compact fluorescent lamps require a ballast to operate, which adds to bulk and size, existing compact fluorescent products are also not shaped to fit in the form factor of a torchiere lamp bowl 50. Up to now there has been no compact fluorescent product to replace the straight halogen-tungsten bulb in existing torchiere style lamp fixtures.
Additionally, virtually all of the halogen-tungsten torchiere fixtures sold have a dimmer switch incorporated in them. Fitting a ballast for a compact fluorescent into the torchiere form factor is further complicated if the ballast also needs to be compatible with the common dimming switches used in halogen torchiere fixtures.
Also, modern compact fluorescents are designed to produce a more compact bulb with higher wattage. As the loads on the surface of the fluorescent tube increase, this causes the wall temperature of the compact fluorescent tube to increase. If wall temperature grows too high, the mercury vapor pressure in the tube, in turn, becomes very high which causes the overall light efficiency of the compact fluorescent to decrease. In conventional compact fluorescents, a cool point on the tube is created by structuring the appearance of the tube to include such a feature. However, this usually means the area of the cool point is small, and thus its cooling effect is limited. If such a tube is placed in a more confined area than the one for which it was designed, the cool point may not be sufficient to keep the mercury vapor pressure in the more optimal range. Thus, attempts to design a compact fluorescent adaptor for the torchiere style halogen-tungsten fixture encounter not only the problems of contact fit and form factor described above, but also the problems of heat dissipation and mercury vapor cooling problems.
It is an object of this invention to provide an adaptor for a halogen-tungsten lampholder in torchiere-style lighting fixtures which will allow a compact fluorescent lamp to be used in the fixture instead of the halogen-tungsten bulb.